1. Field of the Invention
The present invention generally relates to a double lock connector and more particularly, to a double lock connector having a rear holder to finally lock an electric terminal, wherein the rear holder can surely engage a housing of the connector.
2. Description of the Related Art
FIGS. 14 and 15 show a prior art double lock connector disclosed in Japanese Patent Application Laid-open No. 8-88042 (hereinafter "JP '042").
Referring to FIG. 14, a double lock connector 41 of "JP '042" includes a male connector housing 42 made of synthetic resin, a rear holder 44 made of synthetic resin and connected to the connector housing 42 by means of hinges 43, and a female electric terminal 45 accommodated in a connector housing 42.
The rear holder 44 is provided with an electric terminal locking projection 46 on a front end side thereof to lock the electric terminal 45 and a final engaging projection 47 (FIG. 15) corresponding to the connector housing 42 is also formed on a rear end side of the rear holder 44. Description of a provisionally engaging projection is omitted. As shown in FIG. 15, the connector housing 42 is provided with an opening 48 orthogonally to a terminal inserting direction for receiving the rear holder 44, and an engaging groove 49 corresponding to a final engaging projection 47 is formed at a rear end portion of the opening 48.
With a detached state of the rear holder 44 as shown in FIG. 14, the electric terminal 45 is inserted into the connector housing 42 from the rear. The electric terminal 45 is firstly locked by a resilient locking lance 50 (FIG. 15) of the connector housing 42. Next, the electric terminal 45 is secondly locked by the electric terminal locking projection 46 as shown in FIG. 15 by inserting the rear holder 44 forwardly aslant. In case that the electric terminal 45 has to be released at maintenance work or the like, the final engaging projection 47 is disengaged from the engaging groove 49 by means of forcibly pulling out the rear holder 44 with a jig. In FIG. 15, reference numerals 51 and 52 indicate a mating female connector housing and a mating male electric terminal, respectively.
With respect to the above prior art double lock connector of JP '042, however, there is a drawback that the final engaging projection 47 is apt to be worn or to deform and its engaging strength becomes weak in case the rear holder 44 is iteratively attached and detached, thereby causing easy disengagement of the final engaging projection 47 from the connector housing 42. Also, in case that clearance between the rear holder 44 and the connector housing 42 is large, the final engaging projection 47 is apt to easily disengages from the engaging groove 49 of the connector housing 42. More particularly, in case that an electric wire 53 is strongly pulled, the rear holder 44 is pushed rearward by the electric terminal 45 and is apt to be released from the connector housing 42, thereby causing a lowering of locking strength of the electric terminal 45 and finally causing coming-out of the electric wire 53.